Melt the chocolate in a bain-marie over a mild heat. Wash the strawberries, dab dry. Dip half of them into the chocolate and leave to dry. Cut melon into quarters, remove seeds. Arrange on plates.
Pour the rest of the melted chocolate into a small plastic bag. Cut a very small hole. Pour the chocolate in lines over the melon and plate. Whip the cream until stiff. Sprinkle with vanilla sugar.
Season to taste with lemon peel. Pour into a piping bag with star-shaped spout. Garnish the melon with it. Arrange strawberries and serve.